Preparation of dihaloalkanes and related products

ABSTRACT

Process for the preparation of an alpha-, omega-disubstituted alkane by reacting a vinyl compound such as ethylene with a chlorine, bromine, or cyanide ion in the presence of an inorganic symmetrical per oxygen compound and a metallic ion of Ni 2, Co 2, Mn 2, Tb 3, Nd 3, Pr 3, Fe 2, Cu 2, or Tl 1.

United States Patent [191 MacLean et al.

PREPARATION OF DIHALOALKANES AND RELATED PRODUCTS Inventors: Alexander F. MacLean; Charles C. Hobbs, Jr.; Edward F. Dougherty,

all of Corpus Christi, Tex.

Assignee: Celanese Corporation of America,

New York, NY.

Filed: Apr. 13, 1970 Appl. No.: 31,880

Related U.S. Application Data Continuation of Ser. No. 473,807, July 21, 1965, abandoned.

U.S. Cl. ..260/659 R, 260/465.3, 260/465.8,

260/465, 260/654 R Int. Cl ....C07c 17/00 Field of Search ..260/659 R 10/1965 Heinemann et al ..260/659 R Primary ExaminerLeon Zitver Assistant Examiner-Joseph A. Boska Attorney-Marvin Turken, Kenneth A. Genoni, Stewart N. Rice and Ralph M. Pritchett [5 7] ABSTRACT Process for the preparation of an alpha-, omega-disubstituted alkane by reacting a vinyl compound such as ethylene with a chlorine, bromine, or cyanide ion in the presence of an inorganic symmetrical per oxygen compound and a metallic ion of Ni, Co, Mn, Tb, Nd, Pr, Fe", Cu, or T1.

5 Claims, No Drawings PREPARATION OF DIHALOALKANES AND RELATED PRODUCTS This application is a continuation of Ser. No. 473,807, filed July 21, 1965 and now abandoned.

This invention relates broadly to a method of producing substituted alkanes, particularly, alpha-, omegadisubstituted alkanes. More particularly the invention is concerned with the preparation of alpha-, omega-, dichloro-, dibromo-, or dicyanoalkanes by contacting together a vinyl compound in a medium containing an ion selected from the group consisting of chlorine, bromine, and cyanide ions, in the presence of an inorganic symmetrical per compound, e.g., inorganic persulfate, perphosphate, percarbonate, etc., and a metallic ion selected from the group consisting of Ni, Co, Mn, Tb, Nd, Pr, Fe, Cu, and 11*.

The free radical reaction of vinyl compounds such as ethylene with halogen ions in the presence of an inorganic symmetrical per compound such as inorganic persulfate, perphosphate, percarbonate, etc. has been described in an earlier application by MacLean et al, Ser. No. 316,151, filed Oct. 14, 1963, now US. Pat. No. 3,285,981, and assigned to the assignee of the present case. More particularly, there is described therein a method of producing an alpha-, omegadichloroalkane including 1,4-dichlorobutane by reacting ethylene and sodium chloride together in the presence of potassium persulfate in an aqueous medium under an ethylene atmosphere at superatmospheric pressure.

The present invention is based on the discovery that alpha-, omega-disubstituted alkanes of the kind broadly described above can be obtained in significantly better yields by addition of the specific metallic ions mentioned above to the reaction medium.

Further, it was discovered that certain of the metallic ion catalysts favor high molecular weight a, w-disubstituted alkanes. More specifically, it has been found that the presence of Ni, Co, Ce and the rare earths Tb, Nd, and Pr favor the production of higher molecular weight alpha-, omega-disubstituted alkanes such as the 1,4- and 1,6-disubstituted alkanes, while Fe, Tl and Cu favor the production of the lower molecular weight compounds, particularly the 1,2-disubstituted alkanes. I

In practicing the invention any source of chlorine, bromine, and cyanide ions may be employed. Preferably the source is a water soluble material and is represented by the general formula where M is a metal of Group I, Group II or Group 111 of i the Periodic Table, X is chlorine, bromine, or cyanide and y is an integer ranging from 1 to 3. Advantageously M represents metals such as the alkali metal and alkaline earth metals. More particularly, metals such as sodium, potassium, lithium, cerium, rubidium,'calcium, barium, magnesium, aluminum, antimony and cerium are applicable.

The per compound reactants preferably are watersoluble persulfates including the water-soluble inorganic persulfates, perphosphates and .percarbonates, e.g., the alkali-metal persulfates, perphosphates and percarbonates such, for instance, as sodium, potassium and lithium persulfates, perphosphates and pe'rcarbonates. Also, ammonium persulfate, perphosphate and percarbonate may be used. Illustrative examples, of

, other persulfates that may be employed in this reaction styrene.

Any source of metallic ions of nickel, cobalt, manganese, cerium, terbium, neodymium, praseodymium, iron, copper and thallium may be employed. Preferably the source is a water-soluble material. Illustrative of materials which may be used include the chloride, bromide, cyanide, sulfate, and carbonate salts of the above metals.

It is not fully understood why these catalysts promote this free radical reaction. ,While not intending to be I bound by any theory, it is believed that the catalysts might act in several ways. They could be oxidized more effectively than C1 by S 0 and in turn oxidize C1, or form a higher oxidation state which then initiates polymerization, or further, they could terminate polymerization by transfer of a chlorine, bromine or cyanide group.

The reaction is preferably carried out in the liquid phase, more particularly in an aqueous reaction medium although an organic reaction medium may be used. For example, water alone, or water plus another additive, e.g., an acid or an alcohol such as acetic acid, methanol, ethanol, t-butyl alcohol, or further theaacid or alcohol alone may be used.

The aqueous medium containing the reaction ingredients is usually maintained under an atmosphere of vinyl compound where the vinyl compoundis gaseous at superatmospheric pressure during the reaction period, and, more particularly under a ethylene partial pressure of from about 50 p.s.i. to about 10,000 p.s.i. In any case, the reaction is suitably carried out atabout to 200 p.s.i.g. total pressure. Where thevinyl compound is liquid under the required reaction conditions, a two phase system is formed with the vinyl compound dissolving in the aqueous medium to the extent of its solubility at the particular pressure employed. Similar pressure conditions applicable to ethylene are also'applicable with the other compounds.

The temperature of the reaction may vary, for example, between ambient temperature (about 20 30C.), preferably at least about 40C, and about C.

The reaction may be carried out .by continuous, semi-continuous or batch operation. Depending upon the particular reactants employed, the temperature of reaction and other influencing factors, the time of reaction may vary, for example, from 10 minutes, preferably from 1 hour, to 72 hours or more.

The molar proportions of the substitution ion, e.g. chloride, bromide, or cyanide, and the per compound may be varied considerably. Usually, however, the source of the substitution ion, e.g., an alkali-metal chloride such as NaCl, constitutes from about 1 to 10 moles thereof per mole of per compound. The mole ratio of vinyl compound to per compound in solution is dependent upon the solubility of the vinyl compound in the solution. With respect to ethylene, the ratio of ethylene to persulfate consumed is quite low. (It may even be less than 1.) However, as the dissolved vessel along with a desired amount of pentane. The vessel was placed in a high-pressure rocker bomb. The air in the system was displaced with ethylene under pressure. The mixture was heated at 85C. under 150 psig.

ethylene is consumed in the reaction, additional ethylene for at least 3 hours. The products were exethylene from the atmosphere over the aqueous solutracted in the pentane phase as they formed.

TABLE 1 77777 0.1 M 0.10 M 0.10 M 0.10 M 0.10 M 0.10 M 0.10 M 0.10 .\l 0.10 M 0.10 M 0.10 M 0.10 M 0.10 M 0.10 M 0.10 M 0.10 M 0.10 M 0 10 M 0.10 M 0.10 M 0.10 M 0.10 l

Blank Ni Co C0 3111- Tlfl Nd" lr F0 (u- Tl 0.010 0.010 0.010 0. 010 0. 010 0. 010 0. 010 0. 010 0. 010 0.010 111111111 1)ll 5.0 5.0 1.0 1.0 3.0 1.0 1.0 4.0 1.0 1.0 2.0 FinnlplL... 1.5 1.02 1.0 0.0 1.3 1.5 1.5 1.1 0.0 1.1 1.11

ltl't'tlll. conversion KgSgOs lo '1 oHQ)-.c1 5.1 5.5 3.5 5.5 3. 0 1.2 1.11 -1. 0 50.2 51. 0 20.1

CKCIl hHJL. (1.5 0.8 0.1! 0.8 0.2 0.8

Total conversion i V 13. 7 32. 3 l0. 5 31.2 18. 3 11).! 20. 5 21.0 5!|.l 55. l 55- 3 tion dissolves thereby maintaining a supply of this reac- From the examples in Table I it can readily be seen tant in the solution without having a large amount disthat the ratio of the l,4-, 1,6- and 1,8-dichloroalkanes solved at any one time. to that 1,2-dichloroalkane is significantly greater in the The molar proportions of the metallic ion catalyst case of Ni, Co, Ce, Mn, Tb, Nd, and PP may also be varied considerably. Usually the metallic than Fe, Cu, and Tl when these are present in the compound added as the source of metallic ions is reaction medium. present in the reaction medium in amounts of less than It will be understood, of course, by those skilled in 0.5 mole of per compound and generally less than 0.1 the art that the present invention is not limited to the mole per mole of per compound. specific ingredients, proportions thereof, time and tem- When the reaction is carried out in an aqueous reacperature of reaction and other operating conditions tion medium as is the preferred technique, the alpha-, given in the forgoing detailed description and examples omega-disubstituted alkanes that are formed separate by way of illustration. as a distinct liquid phase since they are insoluble in and We claim: heavier than the aqueous phase. If desired, an amount 1. The process for the preparation of l,4-dichlor0buof'a stable ether compound such as dibutyl ether or tane and 1,6-dichlorohexane which comprises reacting saturated valkyl hydrocarbon sufficient to extract the ethylene in an aqueous medium with Sodium chloride alpha,omega-disubstituted alkanes as they are formed in the presence of potassium persulfate and the metallic may be.added to the reaction medium. The saturated 40 ion catalyst, Pr, under an ethylene atmosphere at sualkyl hydrocarbon may be one having from S to 16 carperatmospheric pressure, the source of said metallic bon atoms such as n-pentane, hexane, dodecane, etc. ion being a chloride, bromide, cyanide, sulfate or car- The compounds resulting from the method of this inbonate salt of the metal. vention are particularly useful in chemical synthesis 2. The process according to claim 1 wherein the because they permit simultaneous reactions at both process is carried out c0ntinuously. ends of the carbon chain. By using various chemical 3. The process according to claim 1 wherein the techniques, there can be produced a series of glycols, reaction is carried out at a temperature ranging diacids, diamines, etc., which are useful per se and also between ambient temperature and 150C. and a presas reactants in other chemical reactions. sure ranging from to 10,000 psi.

In order that those skilled in the art may better un- 50 4. The process according to claim 1 wherein the time derstand how the present invention can be carried into of reaction may vary from 10 minutes to 72 hours. effect, the following examples are given by way of illus- 5. The process according to claim 1 wherein the subtration and not by way of limitation. stitution ion and the per compound are. present in a v The general procedure was as follows: molar ratio of about 1 to 10:1 and the metallic ion An aqueous phase 0.1 M in potassium persulfate, catalyst is present in an amount less than 0.5 mole per 0.40 M in sodium chloride and 0.010 M in the desired mole of per compound. metallic ion catalyst was charged into a cylindrical'glass 0 a: a: 

2. The process according to claim 1 wherein the process is carried out continuously.
 3. The process according to claim 1 wherein the reaction is carried out at a temperature ranging between ambient temperature and 150*C. and A pressure ranging from 50 to 10,000 psi.
 4. The process according to claim 1 wherein the time of reaction may vary from 10 minutes to 72 hours.
 5. The process according to claim 1 wherein the substitution ion and the per compound are present in a molar ratio of about 1 to 10:1 and the metallic ion catalyst is present in an amount less than 0.5 mole per mole of per compound. 